Hi, i don’t know anything about developing FOSS software or building a community but I can provide feedback on how native English speakers react to certain scenarios.
Everything is subjective. what’s appropriate when talking informally to a friend might be quite wrong in a business meeting, but even then, depending on who’s present and whats being discussed, it still might be ok to use quite informal language.
clearly the use of “having balls” originates from the male body part but it is widely used as a general term for being brave. if your going to use less formal language then yes, you can use it with both genders. This is fine.
An interesting alternative is the word “cajones”, This seems to have come into use through North American TV as our English speaking cousins over there picked this up from their Spanish speaking neighbours. Cajones means testicles in Spanish.
“you sure got some cajones!”.
If you really didn’t feel comfortable using balls because of the gender implications then you could always refer to bravery of fortitude by asking if they have “the stomach (or guts) for it.”
in my opinion this is a little more risky. you have to know someone quite well to make a joke about striking them with a penis. myself, if someone interjected with this i’d find it outrageously funny, but for me that’d be because it’s quite close to the line on what’s acceptable.that’s kinda why i’d find it funny.
definitely one to save for people you know and have spoken to many times before.
very succinct. i wouldn’t expect this from the website where i go to moan about my gas bill as explaining it like this is something you’d do in a more social, recreational environment. I think it’s ok to say this here because people come to hang out and relax.
“Hi guys” is absolutely fine, 100% of the time. Your definitely worrying about a non-problem here.
In general, except for the odd asshole, most people would not mind how you say something and are unlikely to be offended IF it’s obvious that what your saying is meant playfully and not meant in a serious way.